Electric clock



F. D. NORTON ELECTRIC CLOCK Dec. 3, 1940.

Filed Dec. 12, 1958 2 Sheets-Sheet l F. D. NORTON ELECTRIC CLOCK Dec. 3,1940.

2 Sheets-Sheet 2 Filed Dec. 12, 1938 Patented Dec. 3, 1940 UNITED STATESPATENT OFFICE ELECTRIC CLOCK Application December 12, 1938, Serial No.245,327 In Great BritainDecember 15, 1937 7 Claims.

This invention relates to electrically actuated clocks and has for itsprincipal object to provide a new or improved method of and means foractuating the chiming and/or striking mechanism.

According to the present invention an electric synchronous motor isprovided which is adapted to impart continuous and regular motion to thehands through suitable gearing in known manner. Such gearing is adaptedto impart, preferably through an intermediate gear wheel, continuous andregular motion to one element of a separable clutch the other element ofwhich is connected to a chime and/or striking drum, the slidable clutchelement or associated part being formed or adapted to function as acounter to govern the extent of the chimes and/or the number of strikesafter the manner of a counting plate associated with a locking memberactuated by or y from the time indicating mechanism and'also adapted toimpart the desired longitudinal movement to effect and maintain theclutch elements in operation until said locking member enters a notch ordepression, so that the chime and/or striking drum are driven, directlythrough the clutch, to the extent necessary to give the desired chimeand/or strike without the necessity for racks, gathering pallets andsnails or the like and attendant gearing.

According to another feature of the invention the chimes mechanism isautomatically set and maintained in correct synchronism with the timeindication, by means of projections or arms on the tappet wheel or thelike on the time element, the length of which are varied to vary themovement of the interconnected mechanism controlling the chiming drum orbarrel, and the surface of the latter or part interconnected therewithcarrying projections or recesses arranged or adapted so as to only beengaged in correct sequence to ensure that the cycle of movement of saiddrum or barrel always corresponds in each hour, to the cycle of movementof the time indication hands.

A convenient method is to provide a clutch element connected to thechiming drum which is mounted so as to be capable of a sliding motion,said drum being formed with projections or recesses spaced apart atintervals corresponding to the amount of motion to be imparted to saiddrum to effect a given chime, said projections or recesses lying withinthe path of a complemental recess or projection on a member movableunder spring pressure or the like normally tending to move the partstogether so that a projection on one member engages a recess on theother member to arrest the movement of the drum, said movable memberbeing controlled by a rocking lever or the like adapted to impart motionthereto when actuated by a tappet wheel or the like rotated continuouslyand uniformly by 5 the time indicating mechanism, said tappet wheelhaving teeth or projections shaped or spaced apart proportionately,relatively to each other, according to the time intervals of the chimingso as to free the drum at the required time inter- 1 val, whereupon thecomplemental projections and recesses move out of register with eachother and immediately upon the release of said rocking arm or the likethe spring pressed member is free to exert itself to impart a slidingmovement of 15 the drum to couple the two elements of the clutch so thatthe chiming drum is revolved for a part rotary motion the length ofwhich is determined by the interengagement of ,the next projection andrecess thereon.

Assuming such drum to be used for chimes for the quarter hours then itis preferred to associate a separate disc or drum,'constituting acounting plate to control or effect the hour strike. Said counting plateis also driven from the time indicating gear and has associatedtherewith the moving clutch element of a second clutch which iscontrolled in like manner to the first, and is preferably interconnectedto the chiming drum to positively prevent rotational movement thereofuntil said drum has finished a complete revolution. This is convenientlyeffected by providing a detent, one end of which engages the countingplate while the other end bears against a snail or cam forming part ofor connected to the quarter chiming drum so that the time in dicatingdrive can move the counting disc which governs the movement of thehammer actuating pin-wheel only when the quarter hour drum has completeda full revolution thereby ensuring no overlapping of the chime andstrike.

In order to ensure that the chimes and/or striking mechanism shall bemaintained in correct synchronism with the time indication theprojections and/or length of arms on the tappet wheel are varied to varythe extent of movement of the interconnected mechanism controlling thechiming drum, and the surface of the latter or part interconnectedtherewith carrying the projections or recesses is arranged so that theylie in diiferent planesor are otherwise adapted so as to only be engagedin correct sequence to ensure that the cycle of movement of said druinalways corresponds in each hour, to the cycle of movement of the timeindication hands.

The invention will be more particularly described with reference to theaccompanying drawings wherein the same reference numerals or charactersrefer to the same thing or part throughout the several views andwherein:

Figure 1 is a diagrammatic front view of a clock showing the inventionapplied thereto only such parts of the clock necessary for a clearunderstanding of the invention being shown.

Figure 2 is an end elevation looking from the left hand side of Figure 1and Figure 3 is a corresponding view looking from the opposite end ofFigure 1.

Figure 4 is an end elevation of the chiming drum detached.

Figure 5 is a detail view showing the gearing for setting the handswhile Figure 6 is a detail view showing in end elevation the countingplate for the hour strike and,

locking member therefor.

In carrying the invention into effect according to one convenient manneras illustrated an electric clock motor I with associated gearing coupledtov the hour and minute hands 2 and 9 respectively is mounted on a clockframe provided with a dial 4 and meshing with said gearing is anothergear wheel 5 or train of gears meshing with a gear wheel 6 formed in onewith or rigidly connected to a clutch element 1 fixedly mounted on aspindle 8 journalled in the framework and having rotatably mountedthereon a drum 9 having projecting pins II! for actuating the hammertrips H of which any desired number may be provided, usually four, (seeFigure 2), for strlk ing the quarter hour chimes, the series of pins l0being arranged on the separate segments of the drum proportionedrelatively to each other to give the correct chime for each quarter inknown matter.

Said drum 9 has formed or attached thereto, at the end adjacent to thefixed clutch element 1, the complemental clutch element i2, said clutchbeing of any convenient type, for example a one way ratchet toothedclutch as shown, the barrel 9 being influenced by a spring I9 located onthe spindle 9 between the two clutch elements normally acting to movethe barrel outwards to separate said clutch elements.

The opposite end face of the drum 9 is provided with a series ofrecesses I4, one in each segment of the drum carrying the separateseries of pins I9 to actuate the given chime, all lying in the samepitch circle in line with which is apeg II adapted to enter therein,said peg being mounted on one arm I6 of a bell crank lever ll pivotallymounted on the frame at l8 normally acting under the pressure of thespring I 9 to move the peg l5 into engagement with one of the recesses Hon the barrel. The other arm l6 of the bell crank lever i1 is acted uponby one end of a rock lever 20 pivotally mounted at 2| on the frame withthe other end lying in the path of a snail or tappet wheel 22 rotated bythe time gearing, said tappet wheel having four arms 23, of which threeare of equal length whilst the fourth is of greater length for a purposehereinafter explained.

The operation of the device is as follows; assuming the motor to bedriving the gearing to move the hands, a like continuous rotary motionis imparted to the fixed clutch element I, the movable element l2forming part of the drum 9 being separated therefrom due to theinterposed spring l9 having moved'the barrel endwise, the frictionaldrive of the barrel due to said-spri g being resisted due to theengagement of the peg II on the lever IS with one of the recesses ll inthe barrel so that no rotation of the chiming barrel takes place.

Continuous rotation of the tappet wheel 22 is also taking place and oneof the short arms 23 thereon tilts the lever 20 which in turn rocks thebell crank lever I! to an extent such that immediately preceding thedisengagement of said arm 29 from the end of the lever 29, that is tosay, at or near the end of the time period, in this instanceone quarterof an hour, the peg I5 is withdrawn from the recess, the barrel 9 thenturning slightly, due to the frictional drive, through the spring l3, tomove the respective recess ll out of register with the pin I! so thatimmediately the end of the rocking lever 20 falls of! the tappet arm 23,the spring l9 retracts the bell crank lever I! with the peg I5. bearingagainst the solid end of the barrel 9, said spring l9 overcoming thespring "so as to push said barrel along the spindle 9 until the clutchelements l2, 1 engage, when the predetermined part rotary movement ofsaid barrel takes place, the longitudinal movement of the barrel movingthe pins l9 into the path of the respective hammer trips II, to causethe pins III, III on the appropriate segment to actuate the gong hammers24 which are carried from the respective hammer trips by the rods 2!,said hammers striking the gong arms 29 as seen more particularly inFigure 1.

At the end of said partrotary movement, the barrel 9 is brought intoposition with the next recess H in register with the peg l5 which enterstherein as said barrel immediately moves in the axial direction, due tothe endwise pressure of the spring l3 so that the clutch elements I, I2separate while the peg l5 entering the recess H prevents furtherrotational movement of the barrel 9 until the next repeat operation, asgoverned by the next tappet arm 29.

Projections 21 on the barrel 9 are provided, one for each recess ll,adapted to engage a stop 28 on the frame to positively limit the turningmovement of the barrel 9 due to friction and serving to move therespective recess l4 out of register with the peg IS, the barrel 9 beingreleased or disengaged from the stops 29 when endwise movea ment thereoftakes place to render the clutch operative, as such endwise movement issuflicient to traverse the projections 21 clear of the stop 29.

The foregoing series of movements takes place for the first threequarter chimes but with the fourth quarter chime the long arm 29" on thetappet wheel 22 gives an increased motion to the rocking arm 29 andconsequently to the bell crank lever I1 and peg l 5 so that the latteris lifted clear of a raised stop 29 which is located on the barrel facebehind the relevant depression l4 and which, (the stop 29) otherwiseprevents the release and rotation of the chime barrel until the minutehand has completed the last quarter of any hour whereby the chimes areself adjusting and self correcting. If desired all the teeth 23 may beof varying length and additional stops 29 of correspondingly variedheight be. placed behind the respective recesses II but it is found thatautomatic rectifying means adapted to function once, if required, duringeach cycle of movement are quite suflicent for practical purposes.

To allow the hands to be manually set, independently of the motor or thechiming barrel, the drive from the motor pinion a through the pinions a,a and a is transmitted to the hands by means of a one way drivecomprising a ratchet wheel (see Figure 5) the pawls 30' for which aremounted on the said pinion a while the ratchet wheel 30 is rigidlymounted on the shaft which carries the minute hand.

The chiming barrel will therefore automatically set itself to thecorrect chime when the peg l5 engages the stop 29 as previouslyexplained.

To strike the hours a second drum or disc constituting a. counting plate33 is provided which is also driven from the time indicating gear inlike manner to the chiming drum. The continuously revolving clutchelement 34 in this case is formed in one with a pinion 35 which isconstantly in mesh with a pinion 5* permanently attached to theconstantly revolving pinion 5 which meshes with the pinion 6 of theclutch element I.

Said clutch element 34 is fixedly mounted on the spindle 36 journalledin the frame work and having rotatably mounted thereon the drum 31 toone end of which the counting plate 33 is secured, whilst at the otherend the complemental clutch element 38 is secured, the barrel 3! andconsequently the counting plate 33 being influenced by a spring 39located on the spindle 36 between the two clutch elements, normallyacting to move the plate 33 outwards to separate the clutch elements.

A second bell crank lever 40 pivotally mounted on the frame at -4l isprovided with an arm 4|) having a pin 42 to engage slots 43 in the plate33 and lock said plate against the frictional drive due to the spring39. The other arm 4|) of the bell crank lever 40 is adapted to bedepressed, against the resistance of the spring 44, by a rocking lever45 whose opposite end 46 is acted upon by a snail or cam surface 41formed on or attached to the chime barrel 9 as seen more particularly inFigure 1.

The combined clutch element 38 and counting plate 33 have rigidlyattached thereto a pinion 48 meshing with a pinion 48 rigid on a spindle53 journalled in the frame and having the pin wheel 5| attached thereto,the gear ratios of the pinions 48 and 49 constituting multiplying gearto impart increased rotary motion to the pin wheel.

The hour hammer 52 is provided wtih a trip end or pallet 53 lying in thepath of the pins or teeth 5| of the pin wheel 5|. The hammer arm 54 isfixed to a spindle 55 journalled in the frame, said spindle beingprovided with a crank arm 56 located below a pendant arm 51 rigid withthe bell crank 40 so that as the arm 4|! is depressed during the initialmovement of an hour strike the arm 51 acting through the crank arm 56imparts a part rotary movement to the spindle 55 which moves the hammerpallet 53 relatively to the re spective tooth 5| so that the countingplate 33 can move slightly, due to the friction drive of the spring 39,immediately the peg 42 is withdrawn from the respective notch 43, suchpart rotarv movement of the counting plate moving the notch out ofregister with the peg, the star wheel 5| also moving until the movementof the combined counting plate and star wheel are arrested due to theengagement of the tooth on the latter with the hammer pallet which hasnot been moved completely clear of the tooth.

When the lever 40 is released from the pressure of the rocking lever 45,the spring 44 causes the lever arm 40 to move towards the counting plateso that the peg 42, which bears on the face thereof, causes endwisemovement of the counting plate element against pressure of the spring 33until said element is clutched to the continuously running gear wheel 35so that rotary movement is imparted to the counting plate to move ituntil the peg 42 is in register with and enters the next notch 43 whenthe counting plate. element is free to move endwise until it isdeclutched by the ac-.

tion of the spring 33.

The motion of the counting plate is imparted through multiplying gear43, 43 to the hammer actuating pin wheel 5| 'and the movement of thehammer pallet 53 relatively to the pin wheel 5|, due to the crank arm56, permits limited free movement of the gear at the commencement of therotating movement of the pin wheel thereby obviating stress on themotor.

The hour striking mechanism can if desired be set to act in correctsequence to the hour hand by depressing the rock lever 4l| manuallyuntil the number of strokes corresponds to the hour as indicated by thehands.

When the desideratum is a striking clock only, no chiming barrel andassociated mechanism is required, the counting plate being actuated inlike manner to the previously described chiming barrel except that thearms to rock the clutch control lever 4|! are suitably modified so as tobe acted upon by means of a twelve-armed tappet wheel or star secured tothe hour wheel one of the said twelve arms being longer than the elevenremaining arms thereof, a stop being provided on the counting plate 33(Figures 3 and 6) the said tappet wheel and stop jointly operating inlike manner to the similar tappet wheel 23 and stop 23 formed upon theend face of drum 9 (Figures 2 and 4). It is to be understood that theself correcting mechanism for the hour strike, may, if desired, beassociated with the chiming clock described in the preceding example sothat the hour striking mechanism is rendered selfcorrecting within themaximum period of twelve hours. The motion of the counting plate is imparted through multiplying gear to the hammer actuating pin wheel asabove described.

By these means electric clocks are provided wherein the chimes and/orstrikes are effectively actuated without the necessity for racks,gathering pallets and snails or the like and attendant gearing, by thecomparatively small synchronous electric motor which is also utilized toactuate the time hands in a sure and certain manner and wherein theparts are readily assembled.

Having now particularly described and ascertained the nature of my saidinvention and in what manner the same is to be performed, I declare thatwhat I claim is:

1. An electric synchronous motor clock embodying visual and audibletime-indicating mechanism comprising in combination an electricsynchronous motor, visual time-indicating means and audibletime-indicating means, constantlymeshing gear wheels to transmit motionto said visual and audible time-indicating means from the motor,separable clutch elements interposed in the constantly-meshing geartrain to the audible time-indicating means, a member adapted to functionas a counter to govern the extent of the audible time indicationsconnected to and intermittently-rotated by the clutch, a springactuatedmember adapted to lock the counter in the stationary position and alsoto move the movable element of the clutch into operative engagement withthe constantly-running element of the clutch, a spring normally tendingto separate the clutch elements, and means actuated by. the visualtime-indicating mechanism to release the locking member, the arrangementbeing such that the locking member maintains the clutch elements inoperation to transmit motion to the counter until said counter is againarrested by said locking member.

2. An electric synchronous motor clock embodying visual and audibletime-indicating means comprising in combination an electric synchronousmotor, visual and audible time-indicating means, a clutch having twoseparable elements, constantly meshing gear wheels to transmit motion tothe visual time-indicating means and also to one element of said clutch,a member adapted to function as a counter connected to the other andmovable element of the clutch, a spring normally tending to separatetheclutch elements, a spring-actuated member normally tending to maintainthe counter in the stationary position and also adapted to move themovable clutch element into engagement with the constantly-runningclutch element when the locking member has been released, and meansactuated by the time-indicating mechanism to release the locking member.

3. An electric synchronous motor clock embodying visual and audibletime-indicating mechanism comprising in combination an electricsynchronous motor, visual time-indicating means, constantly meshing gearwheels to transmit motion to said visual time-indicating means, acounter slidably and rotatably mounted on the frame and provided with aclutch element, a complemental clutch element driven byconstantlymeshing gear wheels from the motor, a spring normally tendingto separate the clutch elements,

a locking member to engage the counter and prevent rotation thereof, amember actuated by the time mechanism to move the locking member out oflocking engagement with the drum, and spring means to cause said lockingmember to impart sliding motion to the counter to cause the clutchelements to engage.

4. An electric synchronous motor clock embodying visual and audibletime-indicating mechanism comprising in combination-an electric sychronous motor, visual time-indicating means, constantly-meshing gearwheels to transmit motion to said time-indicating means, a chimingbarrel slidably and rotatably mounted in the frame and provided with aclutch element. a complemental clutch element continuously driven byconstantly-meshing gear wheels from the motor, a spring-actuated lockingmember to en a e the barrel and prevent rotation thereof. a memberactuated by the time mechanism to move the locking member out of lockingengagement with the barrel, spring means to cause the locking member toimpart sliding motion to the barrel to cause the clutch elements toengage, asprmg normally tending to separate the clutch elements. saidchiming barrel and locking lever being provided with interengagingprojections and recesses functioning as a counter.

5. An electric synchronous motor clock embodying visual and audibletime-indicating mechanism comprising in combination an electricsynchronous motor, visual time-indicating means.

constantly meshing gear wheels to transmit motion' to saidtime-indicating means. a chiming barrel slidably and rotatably mountedin the frame and provided with a clutch element normally held out ofengagement with a complemental clutch element, a complemental clutchelement continuously driven by constantlymeshing gear wheels from themotor, a sprin actuated locking member to engage the barrel and preventrotation thereof, a member actuated by the time mechanism to move thelockin member out of locking engagement with the barrel, spring means tocause the locking member to impart sliding motion to the drum to causethe clutch elements to engage, a spring normallytending to separate theclutch elements,

the chiming barrel and locking lever being provided with interengagingprojections and recesses to govern the period of chime, and means topositively arrest the turning movement of the drum when the lockingmember is released until thelclutch elements engage.

6. An electric synchronous motor clockembodying minute and hour handvisual and also audible time-indicating mechanismcomprising incombination an electric synchronous motor,visual timeindicating means,constantly meshing gear wheels to transmit motion to saidtime-indicating means, a chiming barrel slidably and rotatably mountedin the frame and provided with a clutch element normally held out ofengagement with a complemental clutch element, a complemental clutchelement continuously driven by constantly-meshing gear wheels from themotor, a spring-actuated locking member to engage the barrel and preventrotation thereof, a member actuated by the time mechanism to move thelocking member out of locking engagement with the barrel, spring meansto cause the locking member to impart sliding motion to the barrel toeffect engagement of the clutch elements, a spring normally tending toseparate the clutch elements, the chiming barrel and locking lever beingprovided with interengaging projections and recesses to govern theperiod of chime, to-

gether with means to positively arrest the tuming movement of the barrelwhen the locking member is released until the clutch elements engage,means to ensure that the cycle of movement of the barrel alwayscorresponds in each hour to the cycle of movement of the minute hand.

'7. An electric synchronous motor clock embodying minute and hour handvisual and also audible time-indicating mechanism comprising incombination an, electric synchronous motor, visual time-indicatingmeans, constantly-meshing gear wheels to transmit motion to saidtimeindicating means, a chiming barrel slidably and rotatably mounted inthe frame and provided with a clutch element normally held out ofengagement with a complemental clutch element, a

complemental clutch element continuously driv en by constantly-meshinggear wheels from the motor, a spring-actuated locking member to engagethe barrel and prevent rotation thereof, a member actuated by the timemechanism to move the locking member out of locking engagement with thebarrel, spring means to cause the locking member to impart slidingmotion to the barrel to effect engagement of the clutch elements, aspring normally tending to separate the clutch elements,'the chimingbarrel and locking lever being provided with interengaging projectionsand recesses to govern the period of chime, together with means topositively arrest the turning movement of the barrel when the lockingmember is released until the clutch elements engage, automatic means toensure that the cycle of movement of the drum always corresponds in eachhour to the cycle of movement of the minute hand, a pin wheel andhour-striking hammer, a clutch to impart intermittent movement to thepin wheel, constantly-meshing gear wheels to impart continuous rotarymotion to one element 01' the clutch, a counter associated with themovable element of the clutch, a spring-actuated locking member toengage the counter and prevent rotation thereof, a member actuated bythe chime barrel to move the locking member out of locking engagementwith the hour strike counter,

spring means to cause the locking member to impart sliding motion tosaid counter to effect engagement with the clutch elements and a springnormally tending to separate said clutch elements.

FRANK DAVENALL NORTON.

